Nathan Erickson

University of Saskatchewan | U of S · Department of Large Animal Clinical Sciences

Vaccinations are one of the most impactful tools available to cow-calf producers to control within herd disease and later, in feedlots. While vaccine use has been studied across Canada, inconsistent and variable regional data makes analysis and interpretation difficult. The objective of this study was to describe vaccination protocols and factors a...

Despite growing concern surrounding antimicrobial use (AMU) and the importance of cow–calf herds to the Canadian livestock industry, surveillance of AMU in cow–calf herds to inform antimicrobial stewardship programs has been sporadic. Producers from the Canadian Cow–Calf Surveillance Network (87%, 146/168) provided data and almost all reported AMU...

Objective: To determine if bovine colostrum and sera have antibodies that react with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Animals: Dairy and beef cattle from North America and Europe, sampled before and after the SARS-CoV-2 pandemic. Procedures: Indirect ELISAs using whole bovine coronavirus (BCoV) and SARS-CoV-2; whol...

Objective: This study compares immune and clinical responses of bovine viral diarrhea virus (BVDV)-maternal antibody (MatAb)-positive beef calves primed with intranasal modified-live virus vaccine (MLV) and differentially boosted with a systemic MLV or an inactivated vaccine (KV). Animal: Eighteen commercial Black Angus steers. Procedure: Calv...

Garlic products have been reported to have antimicrobial effects and may trigger anemia in horses, but their direct impact on feedlot cattle has not been detailed. With increased free-choice feeding of garlic-infused mineral supplements to beef cattle, it is important to evaluate this strategy’s impact on the animals’ health and the potential impac...

Conflicting anecdotal accounts from producers about their cattle performance and fly-repellence outcomes while receiving garlic-infused supplements have limited feeding decisions. This study evaluated differences in animal performance and insectifugal outcomes among four groups (26 steers per group) over two years (total = 208 steers). The steers e...

Objective: To identify and quantify potential ergonomic hazards associated with routine reproductive examinations of cattle. Sample: 7 bovine veterinarians. Procedures: Each veterinarian was observed and videotaped during 2 bovine reproductive examination appointments. During each appointment, a force-matching protocol was used to estimate the...

Bovine respiratory disease (BRD) is an economically important cause of morbidity and mortality in beef calves. Control of BRD is most often addressed through "homologous" vaccination utilizing the same injectable modified-live viral (MLV) vaccine for both priming and boosting. Heterologous prime-boosting uses different routes and antigenic forms fo...

Objective: To identify risk factors associated with work-preventing musculoskeletal discomfort (MSKD) in the upper extremities (defined as neck, shoulders, upper back, arms, elbows, wrists, and hands) of bovine practitioners. Sample: 116 members of the Western Canadian Association of Bovine Practitioners. Procedures: Data from a previously des...

Bovine viral diarrhea virus (BVDV) is an important pathogen causally associated with morbidity and mortality, and production losses in both suckling and weaned beef calves. Vaccination for protection against disease caused by BVDV is challenging because of the inhibitory effect of maternal antibodies; however, it is most convenient for beef produce...

Bovine respiratory disease complex is etiologically complex and usually involves co-infection by several agents, including bovine parainfluenza virus-3 (BPIV-3), bovine respiratory syncytial virus (BRSV), and bovine coronavirus (BCoV). Traditionally, vaccines have been tested in seronegative calves infected with a single in vitro-passaged agent, of...

The use of metaphylactic antimicrobials to control bovine respiratory disease (BRD) is under increased scrutiny; therefore, effective immunization is becoming a priority. Stimulation of an effective immune response is challenging because calves are often primed with injectable (IJ) vaccines, in the face of maternal antibodies which can interfere wi...

Bovine respiratory syncytial virus (BRSV) is the leading cause of viral pneumonia in calves, making young passively immune calves candidates for vaccination, and raising issues concerning boosting of neonatally primed responses. To address this, 18, 2-month-old Angus-cross passively immune beef heifer calves that had been primed at birth with a com...

Musculoskeletal discomfort (MSD) is prevalent in large animal veterinarians but little research has been conducted on prevalence of MSD and its impact among Canadian bovine veterinarians. This 2017 survey targeted practicing and retired members of the Western Canadian Association of Bovine Practitioners, and adapted the Nordic Musculoskeletal Quest...

The objective of this study is to determine the effect of calving early as a heifer on lifetime production in western Canada. This study evaluated the longevity and life time production data on 211 individual heifers (data gathered for 16 years) at the Western Beef Development Centre (WBDC), Saskatchewan. Heifers were classified as calving in the f...

To investigate the influence of calving early as heifer on her lifetime reproductive performance and productivity using a western Canadian data set. The average life time number of calves weaned for heifers that calved in the 1st, 2nd, and 3rd 21-day period was 5.4 ± 0.32, 4.5 ± 0.37, and 4.2 ± 0.39, respectively. In terms of weaned calf revenue, P...

The objective of this fact sheet was to investigate the influence of calving early as a heifer on cow longevity and lifetime productivity. We reviewed sixteen years of production records from Western Beef Development Centre and found calving period influenced a heifer’s herd performance with heifers that were born in the first calving period having...

A blinded randomized controlled trial was used to evaluate a multi-modal therapeutic regime for treatment of beef bulls infected with Campylobacter fetus subsp. venerealis (Cfv). Treatment included 2 doses of a commercially available monovalent vaccine and long-acting oxytetracycline applied twice at a 2-week interval with treatment completed 2 wee...

Forty beef cows were reported to show signs of abdominal pain and discomfort over a period of 1 wk. Two of the affected animals died and on postmortem examination were found to be impacted with sand in their abomasum and small intestines. Sand-laden barley silage was found to be the cause of these impactions.

Three experiments were conducted to determine the effects of presynchronization and treatment with equine chorionic gonadotropin (eCG) on corpus luteum (CL) and ovarian follicular development, plasma progesterone concentrations, and pregnancy rates in beef heifers subjected to a gonadotropin releasing hormone (GnRH)-based, fixed-timed AI (TAI) prot...

The objective was to investigate the effect of presynchronization with PGF prior to a Cosynch protocol on estrus synchrony, CL and preovulatory follicle diameters and pregnancy rate following timed-AI (TAI) in beef heifers. Cycling beef heifers (n = 148) were treated with 100 μg GnRH i.m. (Cystorelin, Merial Canada Inc., Victoriaville, Quebec, Cana...